Fish tail bit



NOV. 3, 1 3% s. ROBICHAUX 1,330,074

FISH TAIL BIT Filed July 17, 1928 iii) Patented Nov. 3, 1931 UNITED STATES BOBTHENE BOBICEAUX, OI SABATOGA, TEXAS FISH TAIL BIT Application filed July 17, 1828. Serial No. 293,840.

This invention relates to new and useful im rovementsin a fish tail bit.

ne object of the invention is to provide a bit of the character described which is so constructed that the flushing fluid will be more eflective to cleanse the bit blades of the formation having a tendency to adhere thereto, than is the case with fish tail bits now in common use.

Another object of the invention is to provide a fish tail bit of the character described having a transverse cavity in front of each blade in which the water channels, leading downwardly through the bit, terminate, so that the water will be discharged behind the formation, adhering to the bit, to the end that said adhering formation will be more efi'ecthis invention has particular relation to certain novel features of construction, operation and arrangement of parts an example of which is given in this specification and illustrated in the accompanying drawings, where- Figure 1 shows a side view of the bit, partly in section.

Figure 2 shows an edge view thereof, and Figure 3 shows a transverse sectional view taken on the line 3-3 of Figure 1.

Referring now more particularly to the drawings, wherein like numerals of reference designate similar parts in each of the figures, the numeral 1 designates the bit body whose upper end is reduced forming the shank 2 which is threaded to receive a drill collar, of usual construction, by means of which the bit is attached to a conventional drill stem.

Beneath the body the bit is flattened, forming the blade 3. which is wider than the body and whose lower end terminates in the oppositely curved cutting edges 4, 4 which are slightly flared at their outer sides. On opposite sides of the blade. and above the respective cutting edges are the recesses, or pockets 5, 5 which, preferably, extend transversely of the blade.

There is an axial channel 6, extending downwardly through the shank, body and blade whose lower end branches forming separate channels 7, 7 which terminate in the respective pockets 5, 5. Flushing fluid is forced downwardly, under ressure, through .the'drill stem and through t e channels 6 and 7, and into the pockets 5, 5. As the bit is rotated to pierce the formation in the bore, the cuttings, particularly when gumbo is encountered, will adhere to the forward sides of the cutters and will pass up in front of said pockets and the water forced into said pockets will thus engage behind said adhermg formation and will effectively cleanse the same from the blade.

While I have shown what I now consider the preferred form of the invention it is obvious that mechanical changes may be made therein and I reserve the n ht to make such changes as may be found desirable with in the scope of the appended claims.

What I claim is 1. A fish an b it including a body and a.

flat blade attached to the body, said blade having fluid channels leading downwardly therethrough and terminating on op osite sides of the blade, the lower ends of said channels terminating in enlar ed external pockets, and cutting ed es on t e blade beneath the respective poc ets.

2. A fish tail bit having a flat blade whose lower end terminates in oppositely directed so cutting edges, an external transverse recess forming a pocket in each side of the blade above the corresponding edge, there being water channels in the blade which lead downwardly and terminate in the respective pockets.

3. A drill bit including a body having a substantially flat blade having a pocket in each side thereof, said bit having fluid conducting channels, one terminating in each pocket, a wall of each pocket being disposed opposite and being spaced from, the discharge end of the corresponding channel to deflect the fluid, delivered into such pocket, outwardly from the blade.

In testimony whereof I have signed my name to this specification.

SOSTHENE ROBICHAUX. 

